package com.s4.gulimall.product.service.impl;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.s4.gulimall.product.service.CategoryBrandRelationService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.s4.common.utils.PageUtils;
import com.s4.common.utils.Query;

import com.s4.gulimall.product.dao.CategoryDao;
import com.s4.gulimall.product.entity.CategoryEntity;
import com.s4.gulimall.product.service.CategoryService;
import org.springframework.transaction.annotation.Transactional;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {
    @Autowired
    CategoryBrandRelationService categoryBrandRelationService;
    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1、查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);
        //2、组装成父子的树状结构，stream api处理数据
        List<CategoryEntity> levelMenue=entities.stream().filter(categoryEntity ->
                categoryEntity.getParentCid()==0).map((menu)->{
                    menu.setChildren(getChildrens(menu,entities));
                    return menu;
        }).sorted((menu1,menu2)->{
            return (menu1.getSort()==null?0:menu1.getSort())-(menu2.getSort()==null?0:menu2.getSort());
        }).collect(Collectors.toList());
        return levelMenue;
    }

    @Override
    public void removeMenuByIds(List<Long> asList) {
        //TODO  检查当前删除的菜单是否被别的地方引用
        baseMapper.deleteBatchIds(asList);
    }

    @Override
    public Long[] findCatelogPath(Long catelogId) {
        List<Long> paths = new ArrayList<>();
        List<Long> parentPath = findParentPath(catelogId, paths);
        Collections.reverse(parentPath);
        return parentPath.toArray(new  Long[parentPath.size()]);
    }

    @Transactional
    @Override
    //级联更新所有关联的数据
    public void updateCascade(CategoryEntity category) {
        this.updateById(category);
        categoryBrandRelationService.updateCategory(category.getCatId(),category.getName());
    }

    //递归查找父节点
    private List<Long> findParentPath(Long catelogId,List<Long> paths){
       paths.add(catelogId);
       CategoryEntity byId = this.getById(catelogId);
       if (byId.getParentCid()!=0){
           findParentPath(byId.getParentCid(),paths);
       }
       return paths;
    }

    //递归查找子菜单
    private List<CategoryEntity> getChildrens(CategoryEntity root,List<CategoryEntity> all){
        List<CategoryEntity> children=all.stream().filter(categoryEntity ->
                categoryEntity.getParentCid().equals(root.getCatId())).map(categoryEntity -> {
                    //递归找子菜单
                    categoryEntity.setChildren(getChildrens(categoryEntity,all));
                    return categoryEntity;
        }).sorted((menu1,menu2)->{
            //菜单排序
            return (menu1.getSort()==null?0:menu1.getSort())-(menu2.getSort()==null?0:menu2.getSort());
        }).collect(Collectors.toList());
        return children;
    }

}